Sealant compositions or coating mixtures containing functional silane or siloxane adhesion promotors nonreactive with blocked isocyanates

Claim 1

A sealant composition or coating admixture, comprising: a blend of a blocked isocyanate prepolymer, a functional silane or siloxane adhesion promoter non-reactive with said blocked isocyanate-terminated prepolymer, and an effective amount of a polyimine curing agent or a separate polyamine curing agent capable of curing the sealant composition or the coating admixture, said blend being substantially free of organosilanes which are reactive with said blocked isocyanate prepolymer, said blocked isocyanate prepolymer being made from a polyisocyanate and an intermediate which is subsequently blocked with a blocking agent, wherein said intermediate is a polyether polyol, or a polyester polyol, the amount of said functional silane or siloxane adhesion promoter being from about 0.1 to about 10 parts by weight based upon 100 parts by weight of said prepolymer, and wherein said functional silane adhesion promoter non-reactive with said blocked isocyanate-terminated prepolymer has the formula ##STR5## or a siloxane derivative thereof, wherein R 1 is an aliphatic having from 1 to 16 carbon atoms, a cycloaliphatic having from 4 to 8 carbon atoms, or an aromatic or an alkyl substituted aromatic having from 6 to 15 carbon atoms, wherein R 2 is an aliphatic having from 1 to 25 carbon atoms, or an aromatic or an alkyl substituted aromatic having from 6 to 15 carbon atoms, wherein R 3 , R 4 , and R 5 , independently, is an alkyl having from 1 to 10 carbon atoms, an aromatic or an alkyl substituted aromatic having from 6 to 12 carbon atoms, wherein "a" is 0, 1, or 2, wherein "b", "c", and "d", independently, is 0 or 1, wherein "a"+"b"+"c"+"d"=3, and wherein X is an epoxy group, an isocyanato group, or a ketimine group.